Process for analyzing gases



March 4,1924 v 1,485,757

' .J. ALSBERG ET AL PROCESS'IFOR ANALYZING GASES Filed y 18, 9 2 Sheets-Sheet 1 Jul 1266 fizszwery P w/Z J Ralph Patented Mar. i, 192%.

JULIUS ALSBER-G AND PAUL RALPH, OF CHICAGO, ILLINOIS; SAID RALPH ASSIGNOR T0 SAID ALSBERG.

PROCESS FOR ANALYZING GASES.

Application filed May 18, 1917. Serial No. 169,475.

To all whom it may concern:

Be it known that we, JULrUs ALsBERG and PAUL J. RALPH, citizens of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Processes for Analyzing Gases, of which the following is a full, clear, concise, and exact description.

This invention relates to an improved apparatus for analyzing gases and more particularly to an apparatus of this general character wherein an indication and recordation of the roportion of carbon dioxide in flue gases, last furnace gases, producer gases, etc., is effected automatically and continuously.

One object of the present invention is to provide an apparatus of this type wherein water is employed to draw the gases into the apparatus to be analyzed, said water also serving as the absorbing medium for the carbon dioxide, thereby obviating the use of chemicals for this purpose and hence rendering the operation of the device simple and economical as compared with the more expensive methods now in common use.

Another object is the provision of means whereby the absorbing medium prior to its admission into the apparatus is saturated with all of the constituent gases of the gaseous mixture to be analyzed excepting the one, the percentage of which is to be determined.

Other objects of the invention are the provision of automatic means for controlling the pressure of the gases as they are admitted to the apparatus; the provision of means whereby the temperature of the said gases is made to coincide substantially with the temperature of the absorbing medium; and further to provide an apparatus which shall accurately indicate and record any changes in the volumetric proportions of said gases at substantially the same time at which such changes take place.

Other objects and advantages will be apparent from the following description, taken in connection with the accompanying drawings, wherein the preferred embodiment of the invention is illustrated.

Fig. 1 is a view of the analyzing apparatus shown partly in elevation and partly in section.

Fig. 2 is a view taken on the line 22 of Fig. 1.

Fig. 3 is a View taken on the line 3-3 of Fig. 1.

Fig. 4; is a modified form of apparatus.

Referring more in detail to the drawings, the water supply tank is illustrated at 1, water being conducted into said tank from any suitable source through the intake pipe 2. An overflow pipe is illustrated at 3. In order that the water supplied to the apparatus may be maintained at a uniform pres sure, the tank 1 is of the constant level type, it being provided with a float 1 adapted to operate a valve 5 positioned in the intake pipe 2 to automatically control the supply of water to said tank. Cooperating with the intake pipe 2 within the tank 1 is an aspiratorfi adapted to thoroughly saturate the water with air as the same passes into the tank 1. Suitable bafile plates 7 are shown positioned within the tank 1 and are adapted to separate any excess air from the water after it has passed through the aspirator 6 and prior to its passage through the outlet pipe 8 into the cooling chamber 9. The pipe 8 is provided with a suitable valve 10 adapted to control the pressure of the water as the same passes therethrough.

From the cooling chamber 9, the water is conducted through a suitable outlet 11 into the chamber 12, from whence it flows through the elongated restricted passage or throat 12 leading from the chamber 12, through the pipe 13 and into the separating chamber 14:. The chamber 12 is shown in the drawings as provided with an elongated conical nozzle 15 connected with the gas chamber 16 by means of a suitable temperature equalizer 17, said gas chamber being supplied with a portion of the combustion gases through the pipe 18. A pipe 19 conducts the gas from the chamber 16 into the temperature equalizer 17. The gas chamber is provided with means whereby the pressure of the gases passing therefrom into the temperature equalizer 17 is maintained con stant, said means being shown in the drawings in the form of a valve 20 adapted to control the flow of gases into said chamber 16, said valve being provided with an elongated stem 21, which is shown extending down through the opening 22 in the bottom of said chamber. At the lower end of the stem 21 is attached a suitable balancing weight 23. Rigidly secured to the valve stem 21 above the weight 23 is a pressure controlled member 24 which is adapted to float in the oil or water seal 24. The pressure controlled member 24 is subjected on one side to the pressure within the gas chamber 16, which is usually below atmospheric pressure, due to the suction of the gases from said chamber through the nozzle 15 in the manner hereinafter described. The other side of the member 24 is open to atmospheric pressure. It will thus be noted that varia tions in pressure will cause the float 24 to rise and fall, which motion is transmitted to the valve stem 21 and operates to either cut off the gas supply or to regulate it by opening the valve varying degrees.

It is well known that combustion gases, such as the present apparatus is particularly adapted to analyze, are composed substantially of three constituents, namely, oxygen, nitrogen and carbon dioxide. As above stated, the water, as it enters the system, is thoroughly saturated with air, and accordingly, with oxygen and nitrogen. As the water passes from the cooling chamber 9 through the chamber 12 and the throat 12, it draws gas from the chamber 16 through the nozzle 15 and conveys the same into a separating chamber 14. During this action, the carbon dioxide which forms a part of the gases emitted from the nozzle 15, is ab sorbed by the water, the same being quite soluble therein. The other gases, namely, oxygen, and nitrogen, are not absorbed however, in view of the fact that said gases are much less soluble and since the water, prior to its admission into the chamber 12, has been thoroughly saturated with these gases.

The separating chamber 14, is shown provided with a suitable battle 25 which acts to separate the unabsorbed gases from the water as the same passes through said cham ber 14, said unabsorbed gases rising in the tube 26 which forms a part of the separating chamber 14 to the column of air above the water in said tube. The tube 26 is substantially rectangular in cross section, as shown in Fig. 2, the same being constructed in this manner to prevent the formation of large bubbles within said tube,which would tend to disturb the air column and also to afford a greater radiating surface which aids in the equalization of the temperature between the meager gases and the absorbing medium. The in- 30 into the temperature equalizer 31 and out through the restricted orifice 32.

The water, in which the carbon dioxide has been absorbed, rises in the stand pipe 33 and overflows into compartment 34 of tank 34, after its passage through the separating chamber 14 and around the baflie 25. From this compartment 34, the water descends through the water acket 35 which surrounds the tube 26, through which the unabsorbed gases rise and acts to equalize the tempera ture between said gases and said water. A suitable return pipe 36 conducts the water into the compartment 34" of tank 34, after it has passed through the water jacket 35, from whence it drains off through pipe 37. The temperature equalizer 31 is preferably mounted within the stand pipe 33 and acts to maintain the temperature of the unabsorbed gases passing therethrough and out through the restricted orifice 32 the same as the temperature of the water. The temperature of the restricted orifice 32 is also regulated by the liquid rising in the pipe'33, said orifice being preferably housed within a' suitable chamber 38 through which said liquid circulates. It will thus be seen that ade quate means have been provided whereby the temperature of the unabsorved gases is made to coincide substantially with the temperature of the absorbing medium, which is very essential to a successful and accurate recordation of the carbon dioxide present in the gases being analyzed. The temperature equalizer 31 is shown provided with a. water sealed drain 39, one end of which extends into the tank 34. This seal 39 permits any water which may condense in the temperature equalizer 31 to drain off and overflow into the tank 34. This drain is preferably provided with a suitable valve 44), by which communication therethrough may be cut off in starting the apparatus. This valve also provides means whereby the seal may be filled. The other two branches 41, and 42, of the cross 29, lead respectively to a glass manometer tube 43 and to an indicator and recorder 44. A suitable valve 45 provides means whereby the manometer 43 may be filled and also provides for cutting off access thereto when desired. serves for cutting off the indicator and recorder 44, and the valve 47, mounted in the arm 28 of the cross 29, through which all of the unabsorbed gases pass, provides means whereby said gases may be cut off when starting the apparatus to prevent flooding. The manometer 43 is provided with a suit The valve 46 i til) able scale 48 which is adapted to cooperate therewith to indicate the proportion of carbon dioxide contained in the gas being analyzed.

The operation of the apparatus is as follows: Assuming that combustion gases containing no carbon dioxide are being analyzed, it will be noted that there is no absorption in the chamber 12 or in the throat 12*, as the water draws the g; s in through the conical nozzle 15 and conducts the same into the separating chamber 14. Accordingly, all of the combustion gases drawn through said nozzle 15 will be separated in the chamber 14, and will rise into the air column above the liquid in the tube 26, through the pipe 28 and into the cross 29, through the temperature equalizer 31 and out through the restricted orifice 32. These unabsorbed gases will however, accumulate in the air column until the liquid in the tube 26 has been forced down sufiiciently to result in enough pressure to force the gases out through the restricted orifice 32 as rapidly as said gases rise into said air column. The pressure thus produced, it will be noted, is transmitted to the manometentube 43 and to the indicator and recorder 44, through the branches 41 and 42 respectively of the cross 29, where said pressure acts to cause said instruments to give an accurate and continuous indication of the amount of carbon dioxide present. This reading of the manometer 43 and of the recorder 44 caused by the pressure of the unabsorbed gases, when no carbon dioxide is present in the gas being analyzed, fixes the zero mark of both instruments, thus indicating that there is no carbon dioxide present. On the other hand, should there be any carbon dioxide present in the combustion gases drawn into the apparatus, the same will be absorbed by the water passing therethrough, and as a result, the quantity of unabsorbed gases which are separated in the chamber 14 and caused to rise into the tube 26, will produce a pressure less than the pressure present. when there is no carbon dioxide in the gases being analyzed. Accordingly it will be noted that the manometer reading and the recorder reading will no longer be zero but will indicate that carbon dioxide is present, and also the exact proportion it bears to the other constituents of the gaseous mixture being analyzed. This is due to the fact that the scales cooperating with these instruments are calibrated in such manner as to indicate the various proportions of carbon dioxide present. During the operation of the apparatus, it will be noted that a constant volume of the gas to be analyzed is drawn through the nozzle 15 by reason. of the fact that the water cooperating with said nozzle is under constant pressure, this being controlled by means of the constant level supply tank 1 and the valve 10. The pressure of said gas is also maintained constant, due to the automatic operation of the pressure regulator. Furthermore, means has been provided whereby the temperature of the gas admitted into the chamber 12 is made to coincide with the temperature of the water into which it is drawn, and that means has been provided whereby the temperature of the unabsorbed gases is also regulated prior to the emission of said gases from the orifice 32. Therefore no expansion or contraction of the gases, due to temperature changes, can take place. It follows therefore, that the gas escaping from the restricted orifice is of substantially the same volume as the gas drawn in through the nozzle 15, except for the reduction in volume, which is caused by the absorption of carbon dioxide should there be any present in said gas when the same is admitted to the apparatus. It willthus be seen that a gas analyzer has been provided which will accurately indicate the percent of carbon dioxide present in the gas being analyzed, the discrepancies generally caused in devices of this character by changes in pressure, volume, and temperature of the gas, while it is being analyzed, being reduced to a minimum by the means above described.

In Fig. 4 is illustrated a slightly modified form of gas analyzing apparatus. In this embodiment of the invention, the temperature equalization between the gas drawn into the appa atus and the absorbing medium, is effected in the chamber 12, the equalizer 17 being dispensed with. An apertured plate 49 is positioned in said chamber 12 at the point where the walls thereof begin to converge, said plate being provided with the elongated conical nozzle 50 which corresponds to the nozzle 15 described in connection with the preferred form of apparatus. A second plate 51 is mounted above said apertured plate 49, and forms a cover for the chamber 12. A suitable coiled spring 52 is provided to retain the plate 49 on its seat and the nozzle 50 in proper position in the throat 12. The gas is drawn from the chamber 16 through a coiled pipe 53 mounted in the chamber 12 between the plates 49 and 51, and out through the nozzle 50 into the throat 12* by the absprbing medium, as it flows past said nozzle. The absorbing medium from the tank 1 flows through the chamber 12 around the coiled pipe 53 and thus affords means whereby the temperature of said gas is made to coincide substantially with the temperature of the absorbing medium. From the chamber 12, the water flows through the apertured plate 49 and down around the nozzle 50, substantially as described. The unabsorbed gases are separated from the absorbing medium in the chamber 14, as previously described, and

rise through the tube 26into the cross 29, from whence said gases are conducted through the branch 30 down through the pipe 33 into a jar or other vessel 54, wherein any moisture which may be present in said gases due to their contact with the absorbing medium is removed. To aid in the removal of the moisture from the gases, a small cup-shaped-baiile is mounted below the mouth of the tube 30 in the jar 54, said cup, when partly filled with water, having a tendency to increase the condensation of the moisture, as the gases are deflected therefrom. A stop cock 56 is provided in the bottom of the jar, by means of which the condensed moisture collected therein may be drawn off when desired. The gases, after passing through the jar 54, rise through the pipe 57, also extending through the pipe 33, and escape through the restricted orifice 32 provided at the upper end of said pipe just above the level of the liquid in the tank 84. It will thus be noted that the temperature of the gases passing tl'irough the pipes 30 and 57 is maintained constant by reason of the circulation of the absorbing medium around said pipes as it passes up through the pipe 33. As a further means of maintaining the temperature of the unabsorbed gases and the absorbing medium uniform the vessel 54 is housed within a suitable container 58 through which said ab sorbing medium flows prior to its discharge through the overflow pipe 59. It willthus be notedthat the temperature oi. the gases as they pass through the jar 54, which is submerged inthe absorbing medium within thecontainer 58, will be maintained sub stantially constant.

The branches 41 and 42 of the cross 29, it will be noted, communicate with the manometer 43 and the indicator 44 substantially in the same manner shown and de scribed in connection with the preferred embodiment of the invention. The manomcter in this form of the invention, is shown of slightly modified construction from that illi'istrated in Fig. 1, and comprises a plurality of tubes 43 and 43", the latter of which terminates above the level of the liquid containedin the receptacle 43, while the tube 43 dips into said liquid. It will thus, be noted-that the pressure of the unabsorbed gases will act upon the liquid in the receptacle 43, to force the same up into the tube 43 to various heights corresponding to the proportion of carbon dioxide present. The gas chamber 16 in this form of invention preferably of the same construction as that heretofore described, suitable 1na nometer being provided in connection therewith to provide means for indicating the pressure within said chamber.

The various parts of this apparatus are shown positioned within a suitable housing 61. A cook 62 is provided inthe base of. the chamber 14 toaiford means whereby the liquid usedin the apparatus'may be. drawn off if desired. Another cock 63 is provided which affords means for draining off the liquid from the manometer 43.

If desircd,-the gases emitted from the restricted orifice 32 may also be utilized to indicate the-per cent of carbon dioxide present by conducting said gases to suitable devices provided with slightly modified forms of calibrated scales. It will also be noted that the apparatus herein illustrated and described is not limited in its scope to an analyzation of furnace gases or a carbon dioxide indicator, but is also well adapted for use in analyzing any mixture of gases wherein one of said gases is more soluble than the others in the liquid medium used.

It is obvious that various other changes and modifications may be made in the apparatus as illustrated in the accompanying drawings, without departing from the spirit of the invention, and accordingly, the right is her in reserved to make such changes and modifications .as fairly fall within the scope oi the appended claims.

Having thus described our what we claim as new and desire to secure by Letters Patent of the United States is:

1. The improved method of analyzing a mixture of gases which consists in e'd'ecting the absorption of one of the constituents of said mixture in water and causing the unabsorbed constituents to continuously indicate the proportion said absorbed constituent bears to said unabsorbedconstituents.

2. The improved method of analyzing a mixture of gases which consists in first satuating water with air, then introducingthe n'iixture to be analyzed into said water to effect the absorption thereby of one of the constituent gases thereof, and thencausing the unabsorbed constituents of said mixture to continuously indicate and-record the proportion said. absorbed conti'tuent bears to said unabsorbedv constituent.

The improved method of analyzing furnace which consists in effecting the absorptionof carbon dioxide, one of the constituents of said gas, in water, isolating the other constituents of said gas and causing them to indicate the percent ofcal'bon dioxide present.

4. The improved method of analyzing furnace gas which consists in introducing said gas into a rapidly flowing liquid that is capable of absorbing one of the constitucuts of said gas, thereafter separating the unabsorbed constituents of said gas from said liquid and utilizing the same to indicate the proportion said absorbed constituent bears thereto.

5. The improved method of analyzin invention,

furnace gas which consists in introducing said gas from said liquid and utilizing the said gas into a constantly flowing liquid casame to indicate the proportion said con- 10 pable of absorbing one of the constituents stituent bears to said portion.

of said gas, permitting the said gas to flow In Witness whereof, We hereunto subscribe -1 with said liquid in the same direction for a our names this 10th day of May A. D., 1917.

short interval to thus substantially complete the absorption of said constituent therein, JULIUS ALSBERG. then separating the unabsorbed portion of PAUL J. RALPH. 

